Abstract

Microstructures and mechanical properties of as-cast Cu47.5Zr47.5Al5 bulk metallic glasscomposites are optimized by appropriate remelting treatment of master alloys. With increasing remelting time, the alloys exhibit homogenized size and distribution of in situ formed B2 CuZr crystals. Pronounced tensile ductility of ∼13.6% and work-hardening ability are obtained for the composite with optimized microstructure. The effect of remelting treatment is attributed to the suppressed heterogeneous nucleation and growth of the crystalline phase from undercooled liquid, which may originate from the dissolution of oxides and nitrides as well as from the micro-scale homogenization of the melt.

Received 28 June 2012Accepted 11 September 2012Published online 19 September 2012

Acknowledgments:

This work was supported by the Natural Science Foundation of China (Grant Nos. 51071008 and 51131002), the National Basic Research Program of China (Grant No. 2010CB631003), the Innovation Foundation of BUAA for PhD Graduates and the Fundamental Research Funds for the Central Universities. One of the authors (K.K.S.) is grateful for the supported by the Chinese Scholarship Council (CSC), the National Basic Research Program of China (973 Program 2007CB613901), the National Natural Science Foundation of China (50831003 and 50631010), the Excellent Youth Project of the Natural Science Foundation of Shandong Province (JQ201012). Additional support (J.E.) was provided through the German Science Foundation under the Leibniz Program (Grant EC 111/26-1).

Abstract

Microstructures and mechanical properties of as-cast Cu47.5Zr47.5Al5 bulk metallic glasscomposites are optimized by appropriate remelting treatment of master alloys. With increasing remelting time, the alloys exhibit homogenized size and distribution of in situ formed B2 CuZr crystals. Pronounced tensile ductility of ∼13.6% and work-hardening ability are obtained for the composite with optimized microstructure. The effect of remelting treatment is attributed to the suppressed heterogeneous nucleation and growth of the crystalline phase from undercooled liquid, which may originate from the dissolution of oxides and nitrides as well as from the micro-scale homogenization of the melt.